Kinetic modeling semiconductor deposition

The difficulty facing the reviewer is the almost complete incompatibility between direct kinetic measurements and electronic/compositional studies of metal deposits. Kinetic results have been used to construct models of the surface metal phase with varying degrees of geometric complexity and/or thin film growth mode, but in all cases the metal is assumed a priori to be on top of the semiconductor and to desorb from it in some classical way. Unfortunately, direct measurement of the interface chemistry... 

Studies of the kinetic parameters of thin-film deposition rates and performance are very important to develop appropriate films for solar cell applications. For example, substrate spacing and thin-film yield in CB D of semiconductor thin films have been studied [159] (Figure 5.19). Based on a mathematical model, it was proposed and experimentally verified in the case of CdS thin films that the film thickness reaches an asymptohc maximum with increasing substrate separation. The model takes into account the following several factors ... 

For a synthetic chemist the reaction rate is often the most crucial aspect of kinetics. Synthetic chemistry generally treats reactions in the gas or liquid phase where reactants have high mobilities and where distinct second phases are not normally formed. In semiconductor processing, reaction kinetics such as discussed above is essential to modeling techniques such as chemical vapor deposition (Chapter 12). Solid state chemistry and most materials science of solids is concerned with atomic transport as much as with reactant and product concentrations or thermodynamics. Furthermore, it is often the case that the forward reaction will not occur rapidly until some product is formed. This is normally referred to as a problem of nucleation and is similar to the classic conundrum, which came first, the chicken or the egg In the remainder of this section we will examine nucleation and then turn to diffusion transport kinetics in the following section. 

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